Paper feeding and guiding mechanism for typewriters



Oct. 3l, 1950 J. c. VELTMAN ErAL PAPER FEEDING AND GUIDING MEcHmIsM FORTYPEWRITERS 4 Sheets-Sheet 1 Filed June 24, 1946 IlIooooooooooooooooooooooovooooooo lllllr l I l Il 0ct. 31, 1950 J. c.VELTMAN ErAL 2,527,859

PAPER FEEDING AND GUIDING MECHANISM Foa TYPEWRITERS 4 Sheets-Sheet 2Filed June 24, 1946 n. E fo e m w M45 WMM r M Num e www M 0 cn H oct.3'1, 195o J. C. VELTMAN ETAL PAPER FEEDING AND GUIDING MECHAWISM FORTYPEWRITERS Filed June 24, 1946 i 4 Sheets-Sheet 5 J. C. VELTMAN ET ALoct. s1, 195o PAPER FEEDING AND GUIDING MECHAISM FOR TYPEWRITERS 4Sheets-Sheet 4 Filed June 24, 1946 W .c 5 ..5 ZL r M H M MTM F ELM a W mr /QO w M M Patented Oct. 31, 1950 PAPER FEEDING AND GUIDING MECHANISMFOR TYPEWRITERS John C. Veltman and William y0.. Michelsen, St. Louis,Mo., -assignors to .The Emerson Electric Manufacturing Company, St.Louis, Mo., a corporation of Missouri Application June 24, 1946,`SerialNo. 678,995

s claims. (c1. 19V- 138) This invention relates to improvements intypewriters, and vmore .particularly to improvements in the paper feedand .paper guide for such machines.

Anobject of the invention is to provide irn- .proved, eicient means forholding the paper in printing position, and .to rmly lock the paperagainst the platen in order to permit the paper .sheets to lbe advancedstep by step past the .printing point, thereby vinsuring accuratealignment of the type yon the printing line.

Another object of the invention is to provide f .a'dev-ice of vthe-classmentioned, whereby the pa- -toa proper position for the performance ofthey printing .operation and the advancementof the paper in thecarriage.

Another object oi the .invention is the simplification of adevice of the.type mentioned which is compact and relatively light .in weight,radapting iii-especially for incorporation. in small typewritingmachines of the portable type, and which device may be economicallymanufactured .and assembled. Y

.Additional advantages of the invention will be apparent from thefollowing detailed description thereof taken in connection lwith theaccompanying drawings, in which: y

Fig. l is a top .plan view of the paper carriage assembly with certainof the parts removed to clearly illustrate certain essential elements ofthe invention;

Fig. 2 is a front elevation of the Vcompleted paper carriage assembly;

Fig. 3 is a left end elevation of the ,portion of the carriage assemblyillustrated in Figfl;

Fig. i is a vertical section on the 'line -i of Fig, 2; y

Fig. 5 is a right end elevation .of the portion 'oi the carriageassembly illustrated in Fig. 1;

Fig. 6 isa vertical section on the line of Fig. 2;

Fig. 7 is an enlarged sectional View of the left end of the platen topartly illustrate certain details of the construction;

Fig. 8 is an enlarged horizontal section on the line 8 8 of Fig. 1;

Fig. 9 is Yan enlarged horizontal `section on the line 9-9 of Fig. 1;

Fig. 10 is an enlarged vertical sec-tion on the line yl---Ili of Fig. 2;

Fig. 1l is an enlarged vertical section on the .line l I-II Aof Fig. 2;

Fig. 12 is an enlarged end view -of the paper pan and .the resilientsupport thereof;

Fig. 13 is a bottom plan view of the elements illustrated in Fig. 12;

Fig. 14 lis an exploded perspective vview'of the rightend of the papercarriage assembly;

Fig. 15 is an exploded perspective view of the left end of the papercarriage assembly;

Fig. 16 is a top plan view of theV resilient support for the paper panassembly; and

Fig. 1'7 is a vertical sectional View on the line lll-'Il of Fig, 16.

In the embodiment selected .for illustration, the :invention is shown asincorporated in a paper carriage assembly adapted 'for a typewritingmachine of the por-table type, although `the invention is not 'to beunderstood to be limited in Xits utility to such type of machine.

The carriage assembly generally includes a platen roller Il] mounted onva shaft H. The shaft Il is journaled Vin bearings I2 supported byplates .13,-carried rigidly by the upper lface of an upper rail assemblymember i4, the plates i3 being rigidly .attached `thereto `and extendingvertically upwardly therefrom at Veach end of said upper wall of theupper rail assembly.

-The vplaten roller may be manually rotated by -wheels l5 fmounted,respectively, at each ex- 4'spacing device includes a ratchet wheel-tcarried by one end of the platen shaft.

tremity :of lthe platen shaft Il or, alternatively, by a standard linespacing device. The line I6, A conventional finger lever i1 iscooperativelyy associated with lthe ratchet wheel for imparting a step-by nstep lrotary movement to the ,pl-aten. Inasmuch as thespacing meansis of a conventional type, further description of the details of thislconstruction is unnecessary to an understanding Iof the presentinvention.

The paper lock, release, and guide "mechanism .This paper pan is carriedby the upper rail member of :the carriage assembly, and is mounted to`underlie the platen roller. The curvature of the plate .2B is suchthat, when in assembled 'relation with the platen roller, there will bea slight space between the upper face of the plate and the periphery ofthe platen roller, as best indicated in Figs. 10 and 11 of the drawings.The rear marginal area of the wall 2| of the plate 20 is deectedrearwardly, as shown in these illustrations, and both theiront and rearedges of the plate are rounded, thereby avoiding any sharp surface fromvcontacting with the sheet of paper when the vsheet of paper is insertedand positioned in the machine.

The plate '210 has an elongated slot '22 in the front segment thereof,which slot is centrally positioned in the median area of the plate. Asecond slot 23 is similarly formed in the rear segment of the plate andat each end of these slots are concave depressions 24 and 25,respectively. These depressions constitute seats or bearings for therespective pressure rollers. A pressure roller 26 is mounted in thefront slot 22, and a pressure roller 21 is mounted in the rear slot 23.These pressure rollers comprise cylinders formed of rubber or othersimilar material, through which a metal shaft extends, said shaftprojecting beyond the ends of the rollers to form trunnions which seatin the depressions 24 and 25, respectively, in such a manner as torevolubly support the pressure rollers 26 and 21. These rollers contactthe platen roller I0, respectively, at the front and rear of the lowersegment of the platen roller at the positions best shown in Figs. and 11of the drawings.

The paper pan assembly which carries the pressure rollers is resilientlysupported by the top rail member of the carriage assembly in such amanner as to cause the rollers 26 and 21 to normally press against theplaten roller.

The support for the paper pan assembly comprises a double arm springplate having a central section 28, a U-shaped channel 29 formed thereinat the median line of the plate, and laterally eX- tending arms 30,which arms 3U extend downwardly and terminate in transverse plates 3 Iand on the outer edge of each of which is formed a downwardly projectingear 32.

YThe central portion of the plate has its top face welded or otherwisesecurely attached to the bottom face of the paper pan on a central linethereof so that, when the paper pan assembly is mounted in place, theears 312 will seat in openings 33 formed in the top plate of the upperrail assembly member in spaced relationship. The openings 33 aresufficient in diameter to permit slight longitudinal extension andretraction of the spring.

This structure permits the paper pan to be supported in assembledrelation with the platen roller A in such a manner that it will beresiliently urged upwardly toward the platen roller, the movement beingin substantial parallelism therewith and, likewise, to be depressed witha similar movement. The upward movement of the paper pan assembly movesthe pressure rollers 26 and 21 toward engagement with the platen roller,frictionally locking the sheet of paper therebetween. When the paper panassembly is moved downwardly against the tendency of the supportingspring, the rollers 26 and 21 move out of contact with the periphery ofthe platen roller, which is a released position, permitting freemovement of the paper sheet.' I

In adjusting the paper sheet, and during the movement of the assemblyeither upwardly or downwardly, the transverse plates 3| ride on the topface of the top plate of the upper rail member and serve as a guide toassure that the movement will be in a true vertical path, therebymaintaining the parallelism of the paper pan assembly with the platenroller. This action provides for uniform clearance between the pressurerollers 2B and 21 and the platen roller1 throughout their length.

The mechanism for operating the paper pan assembly to and from lockingposition to either permit free movement of the paper sheet during theadjustment of the same for printing operations, or to locked positionfor frictionally en- `gaging the sheet of paper in feeding operationYthe spring plate.

is extremely simple in construction, but highly efficient in operation.

The actuating mechanism for this purpose comprises a bell crank lever 34which is pivoted upon and is carried by a shoulder screw 35 threadedinto the inner face of the right hand one of the plates I3 of the upperrail member of the carriage, and near the rear of the machine. The bellcrank lever 34 has a nger arm 36 integrally formed with the upper arm ofsaid lever, which finger arm projects upwardly and is inclined forwardlynear the rear right corner of the upper rail assembly, so that it ispositioned for convenient manual manipulation by the operator ineffecting the adjustment of the paper lock and release mechamsm.

A Shaft 31 is mounted in the rear of the upper rail assembly and extendsinwardly from the right end plate I3 to a point approximately at thecenter of the carriage and paper pan assembly. The outer end of theshaft 31 is pivotally supported in a bearing formed in the end plate I3,and the inner end of said shaft is pivotally supported by a bracket 38secured to the top face of the top rail member. Near the inner end ofthe shaft 31 is an arm 39, which has formed integrally therewith a flatextension 40 that projects into the channel 29 formed in the centralportion of There is a small amount of play between the surfaces of theextension 4I] and its seat in the channel 29. This insures that springpressure of the spring supporting the paper pan will be unrestrainedfrom the train of release members by a lock t of these parts.Furthermore, the extension 40 may be easily bent to insure a properseating thereof in the channel 29.

On the outer extremity of the shaft 31, and rigidly secured thereto, isan arm 4I, the upper edge of which constitutes a cam face with a detentor stop 42 at the base. The rearward extremity of the lower arm of thebell crank lever 34 is rounded and is formed to ride on the top face ofthe arm 4I. Thus, when the finger arm 36 is depressed, the extremity ofthe lower arm of the bell crank 34 will cam against the top edge of thearm 4I, thereby rocking the shaft 31 to the limit of the rockingmovement thereof, which occurs at the point of contact when said bellcrank lever arm engages against the detent shoulder 42. When the ngerarm 36 is moved upwardly, the shaft 31 rocks in the reverse direction. Awrap spring 31a coiled on the shaft 31 between the members 38 and 40serves to urge the member 40 upwardly and thereby hold the associatedparts in lock position, avoiding vibration thereof during operation ofthe machine. The upward movement of said finger arm 36 is limited by aninwardly deflected lug 43, formed by bending a section of the upperedge-of the plate I3 inwardly in a position so that the upper arm of thebell crank lever 34 will cont-act therewith before the lower end of saidlever rides over the end of the arm 4I.

The actuating mechanism for raising and lowering the paper pan assemblyjust described forms, in effect, a bail for translating rocking movementof the shaft 31 into a vertical movement of the paper pan assembly, themovement, as hereinbefore described, being accurately controlled topreserve a substantial Iparallelism between the pressure rollers and theplaten roller. Thus, when the finger arm 36 is manually moved forwardlyby the operator, the shaft 31 will be rocked counterclockwise, as viewedin Fig. 14, and. by the mechanism described, thereby draw l from each ofthe plates I3.

rmanipulated into proper adjustment, after which thevnger arm 36 maybesnapped upwardly,.causring engagement of the pressure rollers againstthe sheet of paper and holding it in frictional engagement with theplaten roller.

Since the force for raising and loweringthe paper pan assembly isapplied at a central point Vlongitudinally thereof and the springpressure is applied and released at the approxi-mate center of thelengthy of the spring, the release movement yprevents tilting of thepaper pan assembly, and the reverse movement to locking positionlikewise prevents tilting of the paper pan assembly. Furthermore, sincethe extremities of the paper pan supporting spring with the top memberof the upper rail assembly of the carriage is guided accurately, ashereinbei ore described, a transverse tilting of the paper pan assemblyduring the adjustments thereof is prevented.

The paper feed mechanism also includes a bail whereby sheets of papermay be centered and either curved rearwardly against the platen or bepermitted to extend vertically upwardly parallel with the front face ofthe platen.

This-mechanism comprises a graduated bail rod I) upon which are mountedspaced rollers 5I of conventional design. The bail rod is supported ateach end by left and right arms 5.2 and 53, respectively. The lower endsof said arms are pivoted to the end plates I3 of the upper rail assemblyof the machine carriage. Shoulder screws are threaded into said platesand constitute the pvot mountings for said arms. The upper ends of saidarms 52 and 53 have respec- `tively, inwardly extending sleeves 54 and55 at- Jtached thereto, and the ends of the rod 50 are seated in saidsleeves and adjustably secured therein by lock screws 56.

The bail may be rocked rearwardly to resilientlyurge the rollers 5Itoward the platen, or said bail may be moved forwardly toward a verticalposition, in which adjustment. the sheetv of` paper positioned in the.rear of the rollers 15| will be held in a substantial vertical .positionand guided ina Vertical path in the step` by step feed thereof. 'Thebail 50 is held in its. rearward or its forward adjustment by springs51, which are attached to spring posts 58, which extend outwardly fromthe face of each `of the bail arms 52 and 53. Said springs, at theiropposite ends, are each attached to a spring post 59 extending laterallymoved forwardly over a center position, it is maintained in its forwardposition by abutment of the lower end of the arm 53 -against the platenshaft bearing I2, and by the lower end of the arm 52 abutting against astud 6I on the right hand plate I3. A .push link 62 is pivotally securedto the arm 34 at 63. A screw 64 extends outwardly from the right plateI3 above the platen bearing I2, between which screw and bearing the pushlink extends and is thereby guided between the two elements. When thearm 34 is moved forwardly, the forward end of the push link 62 engageswith the spring post 5B, and moves the bail to forward position out ofengagement with the platen roller. When the arm 34 is in rearwardposition, the bail may be snapped inwardly toward the platen, therebyholding the paper sheet against the upper forward segment of the platenduring printing operations.

From the foregoing, it will be' understood that When the bail is thestructure. illustrated and described fully accomplishes the objectshereinbefore set out and,

also, that while the structure has been described in detail, it willappear that modifications therein may be made without departing from thespirit or scope of the invention.

What is claimed is:

1. In mechanism of the kind described, a platen carriage including ashiftable upper rail member, a platen roller mounted in said railmember, a paper pan mounted between said member and said platen, rollersmounted in said pan to be shifted toward and from the platen roller, anelongated downwardly curved spring `plate attached to the underface ofsaid paper pan normally urging said pan upwardly toward said platen,means guidingly andY removably mounting said spring plate directly onsaid upper rail member, and means for exerting. downward pressure onsaid paper pan. to force the same downwardly to released position inopposition to said spring plate.

2'. In mechanism of the kind described, a platen carriage including ashiftable upper rail member, a` platen mounted n said rail member, apaper pan mounted between said member and said platen, pressure rollersrevolubly mounted in said paper pan, an elongated downwardly curvedspring plate attached to the underface of said paper pan normally urgingsaid pan upwardly toward said platen, means guidingly mounting saidspring plate on said upper rail member includingvertical'projeotionsentering spa-ced openings in said upper rail memberand lateral plates positioned to ride across the upper face thereof, andmeans for moving said paper pan in opposition to said spring plate.

3. In mechanism of the kind described, aplaten carriage including ashiftable upper rail member, a platen ro-ller mounted in4 said railmember, a paper pan mounted between lsaid member and said platenfrollersrevolubly mounted in said pan and spaced circumferentially in respect tothe lower segment of said platen roller, an elongated downwardly curvedspring plate attached to the underfaoe of said paper pan at theapproximate longitudinal center line thereof normally `urging said panupwardly toward engagement with said platen, means guidingly mountingsaidv spring plate on said upper rail member,` and means for forcingsaid` paper pan downwardly in opposition to said spring plate includinga manually manipulative rock shaft, and an arm connected to said rockshaft and extending freely between said paper pan and said spring plate.

4. In mechanism of the kind described, a platen carriage including ashiftable upper rail member having spaced openings in the upper facethereof, a platen mounted in said member in spaced relation thereto, apaper pan comprising a curved plate having a concave upper surfacepositioned between said rail member and said platen, circumferentiallyspaced rollers mount-ed in and movable with saidpaper pan, an elongateddownwardly curved spring plate attached to the underface of said paperpan formed to exert normal.

upward pressure on said pan towards engagement with the. platen, meansguidingly engaging the extremities of said spring plate with said upperrail member including downwardly extending projections `at theextremities of said spring plate mounted in said openings in said upperrail member and being formed to shift endwise therein, and means forexerting downward pressure on said paper pan in opposition to saidspring plate.

5. In mechanism of the kind described, a platen carriage including ashiftable upper rail member having spaced openings intheupper facethereof, a platen mounted in said member in spaced relation. thereto, apaper pan comprising a curved plate having a concave upper surfacepositioned between said rail member and said platen, rollers mounted insaid paper pan, an elongated downwardly curved spring plate attached'tothe underface of said paper pan positioned to exert upward pressure onsaid paper pan at the approximate center line thereof, means guidingly-engaging the extremities of said spring plate with said upper railmember including downwardly extending projections at the extremities ofsaid spring plate mounted in said openings in said upper rail member andbeing formed to shift endwise therein, and lateral projectionscontacting the upper surface of said upper rail member, and means forexerting downward pressure on said paper pan in opposition to saidspring plate.

6. In mechanism of the kind described, a platen carriage including ashiftable upper rail member having spaced openings in the upper facethereof, a platen mounted in said member inY spaced relation thereto, apaper pan comprising a curved plate having a concave upper surfacepositioned between said rail member and said platen, pressure rollersmounted in said paper pan, an elongated downwardly curved spring plateattached to the underface of said paper pan formed to exert normalupward pressure at the center line of said pan, means guidingly engagingthe extremities of said spring plate with said upper rail memberincluding downwardly extending projections at the extremities of saidspring plate mounted in said openings in said upper rail member andbeing formed to shift endwise therein, and means for exerting downwardpressure on said paper pan in opposition to said spring plate includingan arm loosely connected with said paper pan on a line approximately atthe center of the length of said spring plate and a manipulative devicefor rocking said arm.

7. In mechanism of the kind described, a platen carriage including ashiftable upper rail member having spaced openings inthe upper facethereof, a platen mounted in said Ymember in'spaced relation thereto, apaper pan comprising a curved plate having a concave upper surfacepositioned between said rail member and said platen, pressure rollersmounted therein, ran elongated downwardly curved spring plate attachedto the underface of said paper pan formed to exert upward pressure onsaid pan at the approximate center thereof, means guidingly engaging theextremities of said spring plate with said openings in said upper railmember to prevent tilting thereof during movement, and means forexerting downward-pressure on said paper pan in opposition to saidspring plate.

8. In'mechanism of the kind described, a platen carriage including ashiftable upper rail member, a platen mounted in said member in spacedrelation thereto, a paper pan comprising a curved plate having a concaveupper surface positioned between said rail Lmember and said platen,pressure rollers mounted therein, an elongated downwardly curved springplate attached to the underface of said paper pan formed to exert upwardpressure on said pan at the approximate center thereof, means guidinglyengaging the extremities of said spring plate with said upper railmember formed to prevent tilting thereof during movement, and means forexerting downward pressure on said paper pan in opposition to saidspring plate including a shaft pivotally mounted on said upper railmember, an arm secured to one end of the shaft and'loosely engaging thespring plate for downward movement thereof, a cam member secured to theother end of said shaft, and a manipulative member pivotally mounted onsaid upper rail member for engagement with said cam member.

JOHN C. VELTMAN. WILLIAM O. MICHELSEN.

REFERENCES CITED The following references are of record in the le ofthis patent:

